There is quite a bit of speculation when it comes to whether or not mufflers affect gas mileage. The muffler is just meant to keep a car quiet, right? How can hardware meant to muffle sound have any bearing on the efficiency of a vehicle? Well, let’s take a look.

What Is a Muffler?

A muffler, also called a silencer, is part of the exhaust system in a vehicle. Its function is to mitigate the loud noise made by the pistons and valves in the engine. For some, this suppresses one of the coolest things about a vehicle, that roar of power. For many others, a muffler is a necessary part of making sure a vehicle doesn’t become a local annoyance.

Does a Muffler Affect Gas Mileage?

In a word, yes. Having a quality muffler on your vehicle can help to improve its fuel efficiency. To understand how, let’s clear up a few terms.

Economy vs. Consumption

Consumption refers to the amount of fuel a vehicle consumes to go a certain distance at a certain speed. Economy, or fuel efficiency, on the other hand describes the number of miles a vehicle can cover using a certain amount of fuel. By driving conscientiously and using cruise control strategically, you can get better mileage out of your vehicle. While mufflers do not change the amount of fuel your vehicle consumes, mufflers affect gas mileage because they can improve the vehicle’s fuel economy.

How Do Quality Mufflers Improve Efficiency?

Most cars are manufactured with a restrictive exhaust system. Such systems are cheaper to make and keep vehicles quieter than they would be without mufflers. High-quality aftermarket mufflers, on the other hand, allow for better airflow. These mufflers affect gas mileage because they do not restrict the mechanisms of the engine and exhaust valves as much, allowing the engine to breathe easier. 

There are many positive side effects of this diminished restriction. Because exhaust gasses can exit the vehicle more quickly than they could with a default factory muffler, backpressure to the engine is all but done away with and the wasted energy in the exhaust system is reduced. All of this results in better gas mileage for your vehicle. Gas mileage improves not because the muffler adds power, but because the power—already in the engine—can be released at its most efficient. A muffler that is not restrictive allows the engine to breathe.

Is there numerical evidence that mufflers affect gas mileage? The statistic generally cited for muffler-related improvement in efficiency is 2-10%; a quality muffler can increase the economy of your vehicle by 2-10%. On the low end of that scale, if a 3% improvement in fuel efficiency yields a 0.5 mpg gas mileage improvement, you could save $85 on gas over 15,000 miles at  $3 a gallon. At that rate, you could pay off a whole new and more efficient exhaust system in five years. Changing out your muffler can improve the efficiency of smaller vehicles even more dramatically. Obviously, improving fuel economy by closer to 2 mpg can help pay off a new exhaust system in no time.

Other Benefits of a Muffler

The most obvious benefit of quality mufflers is that they are noise dampening. You won’t have neighbors complaining about the rowdiness of your vehicle with an efficient muffler, but the pros don’t stop there. Though there is some debate on whether or not this is always the case, there is evidence that quality mufflers reduce emissions. 

A critical role mufflers play is releasing toxic byproducts and fumes outside of the vehicle instead of letting them seep inside. This protects drivers and passengers while the vehicle is in operation and is the biggest reason that any muffler damage or malfunction should be addressed quickly.

Is Your Muffler Safe?

Just like all the many intricate and interconnected parts of your vehicle, your muffler is subject to wear and tear and hampered performance. That being said, if quality mufflers can improve fuel economy, damaged or faulty mufflers affect gas mileage for the worse. A hole before or in the catalytic converter can allow oxygen to enter the exhaust system and impact its internal pressure. 

If mufflers affect gas mileage, we want to make sure that your muffler is giving you the best bang for your buck. Our team at Layton Car Care is equipped to make sure your vehicle has the best muffler for its needs and that that muffler is working like a charm. If your muffler needs some work, or if you’d like to see your fuel efficiency improve, give us a call today.